Authorities are asking citizens to be careful if they are pulled over and feel uneasy. They advise drivers to call 911 and verify that a legitimate officer is pulling them over or drive to a well-lit, crowded place before stopping, actions permitted under Mississippi state law.

In the Mississippi killings, police believe the suspect may have tricked drivers into pulling over on the highway.

The issue is obviously different from choosing not to pull over just to challenge police. But it begs the question: What can you as a citizen do if you have concerns or suspicions that someone might be impersonating a police officer?

Bill Johnson, executive director at the National Association of Police Organizations, said there are no standard nationwide laws or rules on the issue and every situation is different.

Johnson said that generally, if citizens have concerns, he believes they should try to pull over to a lighted area, or the most populated area they can, to feel more comfortable. But they can also be their own detective. Johnson said that generally, someone impersonating a police officer doesn't have a true marked car.

AnÂ impostorÂ is more likely to be using a car that is similar to the look of patrol cars: Ford Crown Victorias or Chevrolet Impalas, for example. Often they will be legitimate police tucked away on a highway to catch speeders, but you're less likely to find an impostor with an actual stolen police car.

He said drivers should look for specifics: emergency light bars, vehicle decals and even a search light.

In cases such as the current one in Mississippi, Johnson said, police are likely to be more lenient with drivers who take more time to pull over.

"I think in a case like Mississippi where it appears that someone - it may be an active killer out there posing as police - itâ€™s fine if the citizen who is being signaled tries to get on their own phone and call 911 to confirm that it is an actual officer," Johnson said.

And if it occurs in a state where there are laws preventing using your phone while driving, he expects that police would also understand if a motorist did so underÂ circumstances such as in Mississippi.

"Thereâ€™s gotta be some discretion in enforcement when it comes to these circumstances," he said. "If the person has some doubt about the validity of the stop, (or the) car doesnâ€™t appear to be marked properly, I think its fine to try to confirm whatâ€™s going on around them.Â The real police officers in the jurisdiction would understand."

It is probably a good idea to call 9-1-1 to verify that it is the police pulling you over. The problem is that the 9-1-1 call may go to a law enforcement agency that does not have an officer trying to pull you over. If your 9-1-1 call goes to the city police, it could be that the sheriff's office or the highway patrol is trying to stop you. What would a driver be expected to do when he does get a law enforcement agency and they say that they have no officers trying to pull anyone over? I see another dilemma.

Some knew about the red light on cars, but not Dialing 112.
It was about 1:00 p.m. In the afternoon, and Lauren was
driving to visit a friend. An UNMARKED police car pulled up behind her
and put his lights on. Lauren's parents have always told her to never
pull over for an unmarked car on the side of the road, but rather to
wait until they get to a gas station, etc.

Lauren had actually listened to her parents advice, and
promptly called,112 on her cell phone to tell the police dispatcher
that she would not pull over right away. She proceeded to tell the
dispatcher that there was an unmarked police car with a flashing red
light on his rooftop behind her. The dispatcher checked to see if
there were police cars where she was and there weren't, and he told
her to keep driving, remain calm and that he had back up already on
the way.

Ten minutes later 4 cop cars surrounded her and the
unmarked car behind her. One policeman went to her side and the others
surrounded the car behind. They pulled the guy from the car and
tackled him to the ground. The man was a convicted rapist and wanted
for other crimes.
I never knew about the 112 Cell Phonefeature. I tried it
on my AT&T phone & it said, "Dialing Emergency Number."
Especially for a woman alone in a car, you should not
pull over for an unmarked car. Apparently police have to respect your
right to keep going on to a safe place.

*Speaking to a service representative at Bell Mobility
confirmed that 112 was a direct link to State trooper info. So, now
it's your turn to let your friends know about "Dialing, 112"

You may want to send this to every Man, Woman &
Youngster you know; it may well save a life.

Maybe its time for the city/states to quit selling old used police cars at auctions.
Problem as i see it is when they sell them they leave the distinctive black wheels on them and in most cases they leave the search light as well.
In my town alone we have at least 3 carfs that are driven by locals that look exactly like unmarked police cars to include search lights.
Add a couple of flashing lights in the grill and who would know the difference.
If i am being pulled over by an unmarked car i will not stop until i get to the police station.
I will turn on my flashers and proceed to call 911 and let them know i am going to pull over at the police station.
This way there is a record that i never intended to flee the officer.

How is this informative?:
"An impostor is more likely to be using a car that is similar to the look of patrol cars: Ford Crown Victorias or Chevrolet Impalas, for example. Often they [– who? imposters? Impalas? cars? –] will be legitimate police tucked away on a highway to catch speeders, [– d'oh, but relevant how? –] but you're less likely to find an impostor with an actual stolen police car [– than what? a caterpillar in your salad? a blogger with an elementary grasp of grammar and logic? –].

Put on your emergency flasher and lead this police car to a place with enough people. You may even press the panic bottom very briefly just to get some attention. After that, you're really at the mercy of cops, real or fake.

What I love about this article is that NO ONE knows if it was a fake cop. It could have been an "innocent" girl pulled over at the side of the road who killed anyone who stopped to help her. Could be someone who came up behind the drivers and tapped their bumper, doing no damage, and killed them when they pulled over to trade accident info. Maybe those people who were killed already pulled over to nap/urinate/make a phone call and the killer saw them stopped and pulled over too?

This article and people posting comments are giving out fake info, like saying there is a Federal law allowing you not to stop, and that 911 would know if anyone of up to a dozen law enforcement agencies is pulling you over, and people are believing it because it's on CNN's website.

I've been pulled over by the unmarked "white light in the grills" car, and what I learned from experience is that
after you pull into a parking lot or other safe place (not just off to the side of the road),
if you look in your rear view mirror as they turn to pull in after you, you can identify any legitimate decals
on the side of the car – they're usually highly reflective, for what it's worth.
I also learned a marked cruiser often joins them :)

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